SERUM IMMUNOREACTIVE INHIBIN LEVELS IN POLYCYSTIC OVARIAN DISEASE (PCOD) AND HYPOGONADOTROPIC AMENORRHEA

To evaluate the physiological significance of inhibin in various types of amenorrhea, serum immunoreactive (IR)-inhibin levels were measured and compared with those in normal cycling women. Amenorrheic women we re as follows: (1) 23 women with PCOD, 11 women with hypogonadotropic amenorrhea (HA, n=23) and 11 women with regular menstrual cycles. Wome n with HA were further divided into 2 groups according to the presence or absence of withdrawal bleeding (WDB) after progesterone administra tion. HA with WDB was categorized as HA1, while HA without as HA 2. Se rum IR-inhibin levels in women with PCOD were significantly higher tha n those in HA 2 and normal women at days 2 to 5 from the onset of mens truation and significantly lower than those in normal women in the mid -luteal phase. A significant positive correlation was obtained between IR-inhibin and FSH in HA 2 (r=0.681) and HA 1 (r=0.658), but no signi ficant correlation between these two hormones in PCOD and normal women . These results indicated that basal IR-inhibin levels vary with types of amenorrhea. High IR-inhibin levels in PCOD patients suggest that i nhibin plays a part in the discordant gonadotropin secretion in these patients.